Hemipelagic contourites were interpreted in the Silurian Kepingtage （柯坪塔格） Formation in the Tarim basin, Northwest China, through studies of outcrop, core, well-log, and seismic data. They are characterized by t...Hemipelagic contourites were interpreted in the Silurian Kepingtage （柯坪塔格） Formation in the Tarim basin, Northwest China, through studies of outcrop, core, well-log, and seismic data. They are characterized by thin to thick bedded mudstone, with contour current irregularly thin bedded-lentiform siltstone and sandstone. Chitin stone, graptolite, thin-shelled bivalve, dissoconch, and acritatch fossils are present in dark-colored mudstones. A Helminthopsis-Scolicia trace fossil assem-blage was observed in the outcrop and drilling core. Sandstones are mainly well-sorted and subangular-subrounded sublitharenite. Sedimentary structures include oriented current structure, erosional surface, and small-scale cross stratifications. The potential of contourites as hydrocarbon source and reservoir rocks was evaluated on the basis of previous interpretations of paleoclimate and paleosalinity.展开更多
The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in th...The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in the Basque Country,northern Spain.In the hemipelagic section exposed at Zumaia the base of the Selandian Stage has been placed at the base of the Itzurun Formation,ca.49 m above the Cretaceous/Paleogene boundary.At the base of the Selandian,marls replace the succession of Danian red limestone and limestone-marl couplets.The best marine,global correlation criterion for the basal Selandian is the second radiation of the important calcareous nannofossil group.展开更多
基金supported by the National Natural Science Foundation of China (No. 40672078)the Innovative Team Programme of Ministry of Education (No. IRT0864)
文摘Hemipelagic contourites were interpreted in the Silurian Kepingtage （柯坪塔格） Formation in the Tarim basin, Northwest China, through studies of outcrop, core, well-log, and seismic data. They are characterized by thin to thick bedded mudstone, with contour current irregularly thin bedded-lentiform siltstone and sandstone. Chitin stone, graptolite, thin-shelled bivalve, dissoconch, and acritatch fossils are present in dark-colored mudstones. A Helminthopsis-Scolicia trace fossil assem-blage was observed in the outcrop and drilling core. Sandstones are mainly well-sorted and subangular-subrounded sublitharenite. Sedimentary structures include oriented current structure, erosional surface, and small-scale cross stratifications. The potential of contourites as hydrocarbon source and reservoir rocks was evaluated on the basis of previous interpretations of paleoclimate and paleosalinity.
文摘The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in the Basque Country,northern Spain.In the hemipelagic section exposed at Zumaia the base of the Selandian Stage has been placed at the base of the Itzurun Formation,ca.49 m above the Cretaceous/Paleogene boundary.At the base of the Selandian,marls replace the succession of Danian red limestone and limestone-marl couplets.The best marine,global correlation criterion for the basal Selandian is the second radiation of the important calcareous nannofossil group.
